Regenerator wall block



FIG. 1 is a front perspective view of our new and original design for regenerator wall block,

FIG. 2 is a rear perspective view thereof;

FIGS. 3 and 4 are left and right side elevational views thereof, respectively;

FIGS. 5 and 6 are top and bottom plan views thereof, respectively; and,

FIGS. 7 and 8 are front and rear elevational views thereof, respectively.

The broken lines in the FIGURES represent structures in the environment of the claimed design which do not form any part of the claimed design. 

CLAIM The ornamental design for “regenerator wall block,” as shown and described. 